Back in the day, how did they develop for the Intel 4004?

[alank2]

The ROM's were a custom type (4001) and were mask ROM's, so did developers just build their code on paper and have a mask ROM built?

Or did they have to use the 4008/4009 and use a PROM?

 

[Al Kossow]

developmnent details can be found in the documentation http://bitsavers.org/components/intel/MCS4

the way the really early products did development was with a simulator SIM4-02_Hardware_Simulator_Dec72.pdf

I'm a little surprised Dwight hasn't responded, https://www.retrotechnology.com/restore/int_440.html

Here is the way Pro-Log hooked up a 4004 in their programming system

 

[Dwight Elvey]

developmnent details can be found in the documentation http://bitsavers.org/components/intel/MCS4

the way the really early products did development was with a simulator SIM4-02_Hardware_Simulator_Dec72.pdf

I'm a little surprised Dwight hasn't responded, https://www.retrotechnology.com/restore/int_440.html

Here is the way Pro-Log hooked up a 4004 in their programming system

As far as I know, the code was written and simulated on something like a mini computer of that day. The code that one of Gary Kildal's students wrote on some type of assembler, that existed before there was a 4004 based machine. The code I just spoke about was after there were SIM4-01s. Maybe they used a PDP8 or similar. It wasn't written on a 4004 machine.
The first assembler written that ran on the 4004 was by Tom Pittman, as I noted in another post today. As the story goes, Tom wrote it in exchange for one of the SIM4-01 development boards to run the code on. He used the SIM4-01 to printout a mail list for an early computer club. ( I could be wrong but I think it was the Silicon Valley Computer Club )
The SIM4-01 did not use 4001 ROMs. It used 1702 EPROMs. It had a transistor and TTL level translator for PMOS to TTL. There was a TTL circuit to decode the ROM actions for the 4004's multiplexed bus. Some outputs were done using the 4002's and other I/O was TTL ( 4001's can be mask programmed to have inputs or outputs but the 4002 were output only). You can see the circuit in the manual that Al posted.
Al has the assembler on the bitsavers. It is the assembler described in the MCS4 manual.
( Hi Al, I was on a trip and just got back yesterday.)
Dwight